Method of distilling coal-tar or coal-tar pitch and products derived therefrom.



P. c. AEILLY.

METHOD 0F DISTILLING COAL TAR 0R COAL TAR FITCH AND PRODUCTS DERIVED THEREFRDM. AFPLICATION FILED MAR. 28| 15H4.

\ XASMM 'To all 'whom z't may concern:

PETER C. BEILLY,.OF INDIANAPOLIS, INDIANA.

METHOD-0F DISTILLING COAL-TAR OB. COAL-TAB FITCH AND P-BODUCTB VDEBIIVED fTHEREFBOM.

Be it known that I PETER C. REILLY a citizen of the United Indianapolis, in the county of Marion and State of Indiana, have invented certain new and useful Improvements in Methods of lDistilling Coal-Tar or Coal-Tar Pitch and Products Derived Therefrom, of which the following is a specication.

My present invention pertains to an 1mproved method of distilling coal tar or coal tar pitch, and to the products produced thereby.

The method may be successfully carried out by the use of a still such as is shown in the annexed drawings, wherein:

Figure 1 is a longitudinal vertical -sectional elevation of the still and its setting; and

Fig. 2. a front elevation thereof.

One object of the invention is to so treat coal tar that the entire volatile lportion or portions thereof will be carried off, producing certain substances or products 'not heretofore commercially known, `and likewise producing a coke, sponge-like 1n appearance which, along with the products (distillates), has a commercial value.

Various attem ts have heretofore been made to complete y distil coal tar and coal tar pitch (see Lunge, Coal Tm' and Ammonia, 4th edition, 1909, pp. 454, et seg.) but so far as I am aware such attempts have not been successful, and apparently for the reason that one or another part of the still has been allowed to stay cool or relatively so, with the resultant effect that the vaporized matter is condensed and drops back into the mass below, whereas in carrying out my process the still in its entirety is kept at a substantially even temperature. Various forms of stills have likewise been suggested and used, such as brlck, cast 1ron, and wrought iron stills; the first two mentioned are ineffective for well recognized reasons, and as stated by Lunge, (p. 323) Only one material is suitable for tar stills, viz., wrought iron.` Such wrought lron stills have been successfully used 1n the first distillation of coal tar, but where their use has been attempted for the distillation of coal tar pitch it has failed. Thus, in speaking of the distillation of pitch for coke, Lunge, age 454, makes the following observation: The apparently simplest plan, y

States, residing atv Specification of Letters Patent. Patented June 19, 1917,

Application filed March 28, 1914. Serial No. 827,965.

that of carrying on the'process in the tarstill itself to the stage of coke, is not feasible. We have seen, page 323, that cast iron is not well adapted' for tar distilling, and wrought iron would be burnt away too quick y. The brick pitch-ovens, which were sometimes formerly employed will be but briefly mentioned here, as they have not proved practically successful.

In carrying out my vprocess I employ a still so mountedor housed that it is subjected, in its entirety, t0 a substantially even temperature throughout. In other words, the products of combustion which emanate from the furnace pass entirely around the still, and both ends thereof, so that the still, as just noted, is subjected to an even temperature, and the condensation of the distillates within the still is prevented. Apparently, the use of wrought iron stills for the purpose ofcompletely distilling coal tar so as to drive 0E all of the vaporizable elements thereof, and to leave nothing but coke, has not been successful, for the reason that the heat has been applied to the lower portion only of the still. As a consequence of such operation the products which are driven 0H in the lower portion of the still come in contact with the relatively cool upper portion thereof and are thereby congealed and drop back into the lower portion of the still, commingling with the charge therein.

In the drawings, Ihave disclosed a simple form of still and housing or mounting, wherein l indicates the still proper, shown in the form of a cylindrical chamber and provided with a manhole 2 in the upper portion thereof, anda manhole 3 openin into the lower portion of the stillthroug one end or head thereof. A pipe 4 extends from the upper portion of the/still and carries off the products whichare producedffgiwing to the action of the heat, as is well understood. The fire chamberfis indicated by 5, andas will be noted is preferably located adjacent to the front wall 6 of the mounting and over/y said lire chamber I provide a fire arch 7 the products of combustion passing. outwardly through a flue or 'opening 8, formedy beneath said arch and the inner wall 9 of the fire chamber. The outlet for the products of combustion is indicated by 10, and as will be noted, it is located in the rear wall of the mounting, at the lower portion thereof, said operiin dischar ing into a lateral fiue'll, which ue exten s to a stack, which is not shown in the drawings. In practice, a battery of stills is employed, the housing or mountings all being alike and the lateral iue 11 serving all ofthe stills. A fire wall'12 guards the outlet 10, said wall extending well upwardly toward the lower portion of the still so that the products of combustion cannot pass directly from the opening 8 to the outlet 10. Naturally, the products of combustion being the hottest as they emanate'from the openm 8, will rise and come into contact with tie still. As noted, the still is spaced away from the wall of the mounting throughout, and is supported by brackets 13, riveted to the sides of the still and resting in the brickwork or the walls of the stilll housing. rIhus it will be seen that except for the relatively small area of contact of the manholes 2 and 3, the pipe 4, and the-brackets 13, the still is suspended in space in the upper portion of the mounting and is subjected on all sides to the products of combustion passing from the furnace.

With a still thus constructed and mounted, I have been able to completely distil. coal tar upon a large scale commercially. Thus, with a 5000 gallon still, the operation may be concluded in anywhere from eighteen to thirty six hours, dependent upon the nature of the coal tar emplo ed.

During the first portion o the distillation of the coal tar (assuming that coal tar and not coal tar pitch be placed ,in the still), the operation is as usual; that is to say, the water followed by the light oils (phenol group) irst passes over. The heavier oils then pass over, such oils containing naphtha-- lene and the beginning of the 'anthracene These are followed by the anthracene. Such products, of' course,'are well known, and commercially derived from coal tar. From this point on, however, the. method and operation are dierent from those heretofore known. Ordinarily, where the heat is applied merely to the under portion ofthe still, such portion acquires at first a semisolid deposit and finally a solid deposit, practically dry, and to a large degree impervious to heat, so that the liquid mass lying above such coating' or deposit cannot be reached by the heat applied to the bottom of the still. The residue or matter lying above such layer is'still undistilled and conbains a large quantity of volatile matter of a high vspecific gravity, which I have covered contains valuable material, partlcu'- larly for use as preserving compounds for the treatment of wood, with the view of waterproofing the same.

With a still such as herein set forth I am enabled to cause the heatto reach the mass from all directions and to produce a nal Lesoea or ultimate distillation of all the volatile portions, leaving a perfectly dry and easilyremovable coke.

After the anthracene has passed over`,the heat which is applied to the' still is gradually raised to a temperature of substantially 1000 F. At' first, at a temperature of from 7 00 to 800 F. there passes over an orangecolored mass which is waxy at F., and this is followed, when 'the temperature is raised to a proximately 1000 1F., by a substance w ich, when cool, is hard and brittle at 70 F. The latter product, when shaved with .a knife, takes a flaky form, presenting a brilliant garnet color. rIhe surface of the body of material, when so cut, likewise presents a relatively brilliant face, and a similar color. This material has a specific gravity of not less than 1.22 taken at 20 C. rIhe other, waxy material,

' runs all the way from the specific gravity of anthracene, to wit, 1.147, up to 1.22, about which point the color changes from an orange to a garnet color, in the harder material. Both of these products are nonvolatile at ordinary temperatures, and by reason of such characteristic are of great value for preservative and other purposes. Such products, so far as I am aware, are not found in any appreciable quantity as a distillate under any of the processes of distillation heretofore known, and are formed by the cracking o1' decomposition of the material by the heat which I am enabled to apply to the mass as a whole.

If coal tarpitch be placed in the still, the first products passing over will, of course, be 'the heavier oils. Beginning with the heavier oils, the products and residue from coal tar pitch are the same as those from coal tar, and the process of'distillation is the same as above described.

The coke which remains after the distillation is fully completed, is dry and spon elike in appearance, and is easily remova le from the still. The coke may be further identiedby the fact that it presents upon fracture a steel-graysurface upon the lines of fracture, with a brilliant -or glossy surface upon the walls of the depressions, pockets or recesses which appear therein. It is also amorphous,non-crystalline, and sponge-like in appearance. Furthermore, when burned, it leaves a residue of approximately two per cent., composed of noncombustible matter and mineral ash.

The final heavy products above referred to are produced by the decomposition of the material and the moleculair` re-formation thereof after the anthracene has ceased to pass over during the distilling operation.

The use of a still as herein set forth, not

only produces the new materials just speci-- will first be carried over an orange-coloredV tillation of coal tar to produce the ordinary products therefrom, in that 'the heat is ap- 1. The process of distilling coal tar, which I consists in placing a charge thereof in a still; subjecting the entire exterior surface of the stillpto a substantially even temperature;4

and carrying the tem erature to such a high degree as to drive o `all the volatile products from the charge, leaving as a residue within the still a dry coke.

2. The process of'distilling coal tar, which consists in placing a charge thereof in a still; subjecting the entire exterior surface of the still to a substantially even temperature; and gradually increasing the temperature of the still over its entire surface to such a degree as that the nal pro uct driven off will have a specic gravity o not less than 1.22 at 20 C. y

3. The process of distilling coal tar,v which consists in subjecting a charge thereof'in a still to an .even or like temperature over its entire surface, thereby driving off the volatile products fromA the coal tar; and finally,l after the passagepof the anthracene oils from the still, carrying the temperature of the still to approximately 1000 F., whereby there producty waxy at 70 F., and 'afterward a ard, garnet-colored product, brittle at vhard which 4;"'Thg'method of producing a dry coke A:from coal tarpitch andlikewlse producing an orange-colored mass waxy at 70 F. and a garnet-colored mass brittle at 70 F., v

consistsin subjecting the coal tar or coal tar pitch to a'temperature of substantially 1000 F. in a still subjected to a substantially even temperature over its entire surface.

5. As a new article of manufacture, an orange-colored mass waxy at 70 F. and having a specific gravity of from 1.147 to,1.22,

and produced from coal tar or coal tar pitch subjected toa temperature of substantially y 7. As a new artlcle of manufacture, coke produced as the result of the complete distillation of coal-tar, said coke being characlterized'by the fact that it is sponge-like in appearance, amorphous and non-crystalline, is dry, and when burned leaves a residue approximating two per cent. composed of noncombustible matter and mineral ash.

8. As a new article of manufacture, coke produced by the complete distillation of coal-tar, said coke .being characterized by being dry and sponge -like in appearance, amorphous, non-crystalline, and presenting when fractured a steel-gra surface upon the lines of fracture, with a rilliant or glossy surface upon the walls of the depressions,y pockets or recesses appearin therein.

9. That process of comp etely distilling coal-tar, which consists in placing a charge ofthe material in a still; bathing the entire still in a heated atmosphere; and raising the temperature of the same to such a degree as to fractionate and drive off all volatile products'and leaving as a residue within the still, upon ycompletion of the o eration, a. dry coke.

In testlmonypwhereo I vhave slgnedmy name to this specification in the presence of ltwo subscribing witnesses.

' PETER C. REILLY. v

Witnesses:

j Holm A. DODGE,

BnNNm'r S. Jours. 

